1. Field of the Invention
The present invention relates to a bottom end stop for a slide fastener having a two-division type structure comprising a first member and a second member, which are attached to respective fastener stringers opposing each other, and more particularly to a bottom end stop for a slide fastener having a structure facilitating connecting of the first member and the second member, capable of obtaining a sufficient strength as the bottom end stop and providing an excellent appearance.
2. Description of the Related Art
Conventionally, a slide fastener has a top end stop and a bottom end stop provided on ends of fastener elements thereof so as to inhibit a slider from loosing out of a fastener element row. The bottom end stop connects the ends of opposing fastener stringers, thereby preventing the slider from loosing out. Thus, for example, a U-shaped metallic or resin bottom end stop has been used to connect the ends of the opposing fastener stringers, which is a typically employed structure.
In case of such a bottom end stop, however, it is necessary to attach the bottom end stop between the ends of the fastener stringers with a pair of opposing fastener stringers arranged in a line. Thus, this case has a problem that a mounting device specialized for the bottom end stop is required, thereby increasing production processes for manufacturing the slide fastener.
Further, according to another prevailing bottom end stop, instead of using the U-shaped bottom end stop, members constituting a bottom end stop are attached to individual fastener stringers, and after the members are attached, the same members are combined and connected together so as to form a bottom end stop.
According to a method of forming the bottom end stop, for example, each bottom end of the pair of fastener stringers is inserted through a shoulder mouth of the slider, the fastener stringer is moved downward relative to the slider, and the members inserted through the shoulder mouths are connected with each other to form the bottom end stop. As the type bottom end stop, a two-division type bottom end stop and three-division type bottom end stop are available depending on the configuration of the members to be attached to the fastener stringer.
As the two-division type bottom end stop, there have been proposed: a bottom end stop for a slide fastener having a similar shape to a fastener element (refer to U.S. Pat. No. 2,701,401); a bottom end stop for a fastener formed by connecting members constituting the bottom end stop, and then bonding and fixing overlapping portions of the members (refer to Japanese Utility Model Publication No. 59-25217), a bottom end stop of a slider chain in which a stopper for preventing the slider from loosing out is formed on members constituting the bottom end stop (refer to Great Britain Patent No. 1479363) and the like. Further, as the three-division type bottom end stop, a slide fastener with a terminal (refer to Japanese Patent Publication No. 36-19078) has been proposed.
In the slide fastener described in the U.S. Pat. No. 2,701,401, an engaging tooth 51 having protrusions 56, 57 facing in opposite directions on its front and rear surfaces is used as in the perspective view of FIG. 9. Bottom end stops 58 is produced by connecting three engaging teeth 51 through connecting portions 63, 64. Thus, protrusions 60, 61 facing in opposite directions are formed at an engaging head 59 of the bottom end stops 58, 58a. The pitch between the engaging heads 59, 59 is set to the same pitch interval as the mounting pitch interval of the engaging tooth 51, and they are connected with the connecting portions 63, 64.
As shown in FIGS. 9 to 11, the corner portion on the side of the tape side face opposite to the engaging head 59 in each engaging tooth 51 is chamfered. Likewise, in the bottom end stops 58, 58a formed by connecting three engaging teeth 51, the corner portion including the portion between the connecting portions 63, 64 on the side of the tape face is chamfered.
FIG. 10 shows a state in which by inserting the bottom end stops 58, 58a of fastener stringers 52, 52 through shoulder mouths of a slider 53 and then moving the slider 53 upward, the bottom end stops 58, 58a have begun to be connected with each other. In a state in which the same bottom end stops 58, 58a have begun to be connected with each other, the bottom end stops 58, 58a are guided to an enlarged width portion in a flange portion 54 of the slider 53 while maintaining their straight configurations and connected with each other successively from the bottom end side. At this time, part of the side edges of the fastener stringers 52 provided with the bottom end stops 58, 58a is deformed, so that the bottom end stops 58, 58a can escape to the sides of their opposing faces. Consequently, the bottom end stops 58, 58a are connected with each other successively while maintaining their straight configurations.
Since the bottom end stops 58, 58a have begun to be connected with each other, as the slider 53 rises, the engaging teeth 51 are connected with each other successively as shown in FIG. 11. When the slider 53 descends, the connection between the engaging teeth 51 is released by a wedge operation of a neck portion 55 of the slider 53, and the neck portion 55 makes contact with a top face of the head 59 of the bottom end stop 58a, thereby preventing the slider 53 from loosing out.
The bottom end stop for a fastener described in the Japanese Utility Model Publication No. 59-25217 is formed by connecting a long first sub-body and second sub-body. Steps are formed on opposing faces of the first sub-body and second sub-body. When the steps overlap, a protrusion (not shown) formed on the top face of the step on one side and a concave row (not shown) formed in the bottom face of the step on the other side engage each other.
A curved concave portion corresponding to the maximum curved portion of the guide flange of the slider is provided on each tape side face of the first sub-body and second sub-body. Then, by inserting the bottom end portions of the fastener stringer through the shoulder mouths of the slider and then pulling the fastener stringer downward with respect to the slider, the first sub-body and second sub-body can be guided along the enlarged width portion of the flange, thereby engaging the first sub-body and the second sub-body.
Because the first sub-body and second sub-body are provided with the curved concave portion, respectively, an interference with the maximum curved portion in the guide flange can be prevented by the same curved concave portion. Consequently, the first sub-body and second sub-body can pass between the maximum curved portions in the guide flange smoothly.
As the first sub-body and second sub-body pass between the maximum curved portions in the guide flange, the first sub-body and second sub-body can be engaged with each other successively. After the first sub-body and second sub-body are engaged with each other completely, they are bonded and fixed by applying fusing means such as ultrasonic thermal melting means to the overlapping stepped portions.
The bottom end stop of a slider chain described in the Great Britain Patent No. 1479363 is constructed of a pair of bottom end stop members. The pair of bottom end stop members can be fixed by engaging stop elements formed on opposing faces with each other. A slider stopper member is formed on the pair of bottom end stop members so as to be expanded toward the slider.
To construct the bottom end stop by engaging the pair of bottom end stop members, the fastener stringers are inserted through the shoulder mouths of the slider, and the fastener stringers are pulled downward. At this time, each stopper member is deformed elastically inward by the flange portion of the slider and then contracted so as to allow the slider to pass through. After the slider passes each stopper member, the stopper member is restored to its expansion state by its elasticity and is expanded outward. When the slider is slid downward thereafter, the bottom end portion of the slider makes contact with each expanded stopper member, thereby preventing the slider from loosing out.
The slide fastener with the terminal described in the Japanese Patent Publication No. 36-19078 has the structure shown in FIGS. 12 and 13. That is, the bottom end stop shown in FIG. 12 comprises terminal members 75, 76 and 77. The terminal member 77 is mounted to a piping 73 of a fastener stringer 71 by pressure forging or mold forging, and the terminal members 75 and 76 are mounted on a piping 73 of a fastener stringer 72 by pressure forging or mold forging.
The bottom ends of the fastener stringers 71, 72 provided with the terminal members 75, 76, 77, engaging teeth 74 and the like are respectively inserted through shoulder mouths of a slider 96 as shown in FIG. 13, and moved along a guide path formed by flanges 97 and a diamond 95 of the slider 96. Consequently, the connecting between the terminal members 75, 76 and the terminal member 77 is carried out, and the engaging teeth 74 are connected successively. FIG. 12 shows an enlarged view of major portions indicating the connecting of the terminal members 75, 76, 77 and the engaging teeth 74.
A projected portion 78 of the terminal member 76 is coupled with a concave portion 79 in the terminal member 77, and a projected portion 80 of the terminal member 77 is meshed with a concave portion 81 in the terminal member 76. The concave portion 82 of the terminal member 77 extends from the top portion of the terminal member 77 to an intermediate portion of the member 77 so as to form a support face 83, meshing with a projected portion 84 of the terminal member 76. Further, a projected portion 85 is formed on the top face of the terminal member 77 so as to be extended up to the central portion of the member, and further, another projected portion 86 is formed on the bottom portion of the terminal member 77 such that it rises in the center thereby forming a support face 87.
A concave portion 88 having a support face extending up to the middle is formed in the bottom portion of the terminal member 75, and the projected portion 85 of the terminal member 77 makes contact with the same concave portion 88 and is supported by a support face 89. In addition, a projected portion 92 and a concave portion 93 are formed in the terminal member 75, and the projected portion 92 and concave portion 93 mesh with the bottom face side of the engaging tooth 74.
According to the bottom end stops 58, 58a described in the U.S. Pat. No. 2,701,401, the bottom end stops 58, 58a are guided to the enlarged width portion in the flange portion 54 of the slider 53 while maintaining their straight configurations and then, connected with each other successively from the bottom end side. Also, the protrusions 60, 61 each having a predetermined thickness are formed in opposite directions at the front and rear portions of the engaging head 59. Consequently, there is provided a constitution capable of bearing a force applied in the width direction and a force applied in the direction to the front/rear surfaces.
However, because the projected portions 60, 61 having the predetermined thickness in the engaging head 59 are of the same shape, the projected portions 60, 61 need to be deformed largely in order to connect the bottom end stop 58 with the bottom end stop 58′, and for this purpose, a large force is necessary. Moreover, by deforming the projected portions 60, 61 having the predetermined thickness largely, there occurs such a problem that a root portion of each of the projected portions 60, 61 is destroyed, so that a sufficient strength as the bottom end stop cannot be maintained.
Because, when the bottom end stop 58 and the bottom end stop 58a are connected with each other, the bottom end stops 58, 58′ are connected with each other while maintaining their straight configurations, part of the side edges of the fastener stringers provided with the bottom end stops 58, 58a is deformed excessively. Thus, there is such a problem that the mounting positions of the bottom end stops 58, 58a on the side edge of the fastener stringers 52, 52 are deflected because of an excessive deformation of the side edge.
Further, because the bottom end stop 58 and the bottom end stop 58a are formed in the same shape, when the bottom end stop 58 and the bottom end stop 58a are connected with each other, there occurs a difference of step between the right and left sides of the bottom end as the bottom end stop as shown in FIG. 11, which is an undesirable configuration from the viewpoint of the appearance of the slide fastener.
According to the bottom end stop described in the Japanese Utility Model Publication No. 59-25217, a difference of step in the direction of the front and rear surfaces is formed between the first sub-body and the second sub-body, and the protrusion formed on the top face of the step on one side overlaps the concave row formed in the bottom face of the step on the other side such that they are engaged. Further, in order to prevent these overlapping stepped portions from being separated by an external force, the stepped portions need to be fixed by using such fusing means as ultrasonic thermal melting for the stepped portions.
Thus, to construct the bottom end stop, the fusing step is required, and pulling in the width direction of the fastener tape, that is, in the right and left direction sides of the fastener tape is resisted by only a fusing force. For the reason, unless the fusing is carried out securely, the strength against the pulling in the right and left directions is insufficient thereby causing a destruction, which is a problem to be solved.
Although the bottom end stops disclosed in the U.S. Pat. No. 2,701,401, Great Britain Patent No. 1479363 and Japanese Patent Publication No. 36-19078 are capable of solving the problem which occurs in the Japanese Utility Model Publication No. 59-25217, the bottom end stop described in the U.S. Pat. No. 2,701,401 includes the above-described problem. In the pair of bottom end stop members described in the Great Britain Patent No. 1479363, the hook-shaped coupling heads formed on opposing faces of the pair of bottom end stop members are projected toward the mating members which mesh with those hook-like shapes.
Therefore, to combine the coupling heads described in the Great Britain Patent No. 1479363 with each other, engaging pieces of the coupling head need to be deformed largely. To deform the engaging piece of the coupling head largely, a large force is necessary. To generate a large force, the coupling heads cannot be slid smoothly with respect to the flange portion of the slider. Moreover, there exists such a problem that a crack occurs at the root portion of the engaging piece because of deformation by a large force or a crack occurs at the root portion of the coupling head itself, so that no sufficient coupling strength can be secured in the engaging piece and coupling head.
In the bottom end stop described in the Great Britain Patent No. 1479363, the stopper members for preventing the slider from loosing out need to be formed in each of the pair of bottom end stop members. Further, because of the constitution which prevents the slider from loosing out with only the stopper member, tearing resistance necessary for blocking the slider weakens gradually as the slider loosing preventing operation is repeated, and by repeating the slider loosing preventing operation, the stopper member can be ruptured near the root portion thereof.
In the bottom end stop described in the Japanese Patent Publication No. 36-19078, the projected portion from one terminal member and the projected portion from the other terminal member are formed to face in opposite directions. Therefore, the projected portion 78 of the terminal member 76 is largely rotated with respect to the projected portion 80 of the terminal member 77, whereby the projected portions can be engaged with each other, and the projected portions 78, 80 can be engaged with each other without deforming largely. However, because only one pair of projected portions engage, the engagement of the pair of projected portions is released easily if a rotation opposite to a rotation for engagement is applied, which is a problem which should be solved.
In addition, because the terminal member 75 and the terminal member 76 to be mounted on the fastener stringer 72 are disposed with an interval, they can be passed through the maximum curved portion in the flange 97 of the slider 96 in a state in which the straight configuration is maintained as shown in the U.S. Pat. No. 2,701,401 and Japanese Utility Model Publication No. 59-25217.
However, the terminal member 75 for preventing the slider from loosing out and the terminal member 76 for connection in order to fix the bottom end stop are constructed separately with an interval. Therefore, when the fastener stringer 72 is pulled in the right and left directions, the terminal member 75 and the terminal member 76 are moved independently depending on how the force for pulling in the right and left direction sides is applied, so that a resistance force against the pulling force in the right and left directions is weakened. Furthermore, the terminal member 75 and the terminal member 76 cannot make a sufficient contact with the diamond of the slider depending on the arrangement positions of the terminal member 75 and the terminal member 76 and the diamond rides over the terminal member 75, thereby not performing the slider loosing preventing operation sufficiently.
Further, the terminal member 75 and the terminal member 76 having a different shape need to be mounted on the piping 73 on the fastener stringers 72 with an interval, and additionally, positioning thereof with respect to the terminal member 77 attached to the piping 73 on the fastener stringer 71 takes long time and much labor.
An object of the present invention is to solve the above-described problems and provide a bottom end stop for a slide fastener having such a structure which facilitates connection of a first member and a second member to be attached to a pair of fastener stringers and having a sufficient strength as the bottom end stop and an excellent appearance.